Cleaning Polluted Oceans: Is It Possible?

The oceans are under threat. Human activity has led to marine pollution, which is a complex mixture of plastic waste, toxic metals, manufactured chemicals, oil spills, urban and industrial waste, pesticides, fertilizers, pharmaceutical chemicals, agricultural runoff, and sewage.

The majority of marine pollution comes from land-based sources, with rivers being a major contributor. Plastic waste is the most visible component of ocean pollution, with an estimated 75 to 199 million tons of plastic polluting our oceans. This is a result of humans recycling only nine percent of plastic waste and dumping 10 million tons of it into the seas each year.

The consequences of marine pollution are dire. It is estimated that marine plastic pollution may be costing the world economy trillions of dollars every year due to its impact on fisheries, coastlines, tourism, marine life, and the food we eat. It also poses risks to human health, with toxins in the oceans imperilling the well-being of over 3 billion people.

To address this global issue, efforts are being made to clean up the oceans and reduce plastic pollution. However, preventing further pollution and protecting vulnerable human populations and ecosystems is critical.

The impact of plastic pollution on marine life

Marine life is facing a grave threat from plastic pollution. With over 75 to 199 million tons of plastic in the oceans, this pollution is deadly to ocean wildlife. The impact of plastic pollution on marine life is extensive and devastating.

Plastic pollution affects all marine ecosystems and is a significant contributor to biodiversity loss and ecosystem degradation. Marine animals, from the smallest fish to the largest whales, are all at risk. Plastic debris injures and kills marine life, including fish, seabirds, and mammals. It has impacted at least 267 species worldwide, including 86% of sea turtle species, 44% of seabird species, and 43% of marine mammal species. The primary cause of death is ingestion, leading to slow and painful starvation, while entanglement can result in loss of limbs and even death.

Sea turtles, for instance, struggle to differentiate plastic from prey, often consuming plastic bags and other debris. Seabirds are also highly susceptible to ingesting plastic, with one study finding that approximately 98% of chicks sampled contained plastic. This ingestion of plastic has led to the coining of a medical term, "plasticosis," which refers to plastic-induced fibrosis caused by the rough edges of plastic debris that can lead to internal injuries and scarring in seabirds, making it difficult for them to digest food.

Additionally, plastic pollution transports invasive species, which is one of the leading causes of biodiversity loss and species extinction. It also releases toxic chemicals, such as those found in fireproofing coatings, into the soil and water, affecting both ecosystems and human health. These chemicals have been linked to developmental, reproductive, neurological, and immune disorders.

To address this crisis, it is essential to reduce single-use plastics, promote recycling, and foster sustainable practices. Efforts like beach cleanups and the development of new technologies to intercept and remove plastic from oceans and rivers are also crucial in mitigating the impact of plastic pollution on marine life.

The impact of plastic pollution on human health

Plastic pollution poses a serious threat to human health at every stage of its lifecycle, from extraction to disposal. The toxic chemical additives used in plastic production have been linked to a range of adverse health effects in humans, including cancers, lung disease, birth defects, reproductive issues, endocrine disruption, impaired cognitive function, and childhood cancer.

Exposure to Toxic Chemicals

The most commonly used plastic products carry toxic chemicals that can be easily inhaled and ingested by humans. When plastic waste is incinerated during the disposal stage, these chemicals are dispersed into the air, contaminating water and soil, which is lethal to anyone who comes into contact with them. Ocean waves and sun radiation further break down plastics like water bottles into microplastics, which float in the environment, carrying these toxic chemicals, which are then consumed by people through food, water, and air.

Health Effects of Plastic Pollution

Studies have shown that microplastics can significantly damage cells in the human body, leading to cancers, lung disease, and birth defects. Toxic chemical additives in plastics can alter hormone activity in the human body, disrupting reproduction, growth, and cognitive function. Microplastics have also been found to act as vessels for pathogens to enter the human body, increasing the spread of diseases.

Vulnerable Groups

Children, infants in the womb, and marginalized communities are particularly vulnerable to the harmful effects of plastics. Exposure to plastics has been linked to increased risks of birth complications, impaired lung growth, and childhood cancer.

Global Impact

The global cost of plastic-related health effects is significant, estimated at $100 billion per year in 2022. The United States is one of the top contributors to plastic waste globally, and the difficulty of removing plastic from the environment once it has entered ecosystems makes the impacts of plastic pollution on human health particularly concerning.

The impact of agricultural pollution on marine life

Agricultural runoff also contributes to the proliferation of microplastics in the ocean. These tiny plastic particles, which come from sources like synthetic clothing and personal care products, are ingested by marine animals, causing reproductive issues, stunted growth, and tissue inflammation. They can also enter the human food chain, with potential unknown impacts on human health.

In addition, intensive farming practices have negative consequences for the marine ecosystem. Runoff from barnyards and feedlots can introduce harmful bacteria and toxins into the water, leading to toxic algal blooms that smother plants and animals on the seabed. The waste produced by intensive fish farming further pollutes the water and contributes to the destruction of marine habitats.

Agricultural pollution also has indirect effects on marine life. For example, research suggests that nutrient pollution from agricultural land can alter the sounds made by marine life, potentially disrupting navigational cues for fish and other sea creatures.

Overall, the impact of agricultural pollution on marine life is extensive and complex, highlighting the urgent need to address these issues through improved farming practices, regulations, and sustainable solutions.

The impact of agricultural pollution on human health

Agriculture has a profound effect on the planet and human health. Modern agriculture has allowed for the growth of civilizations and supported an exponential boom in the human population. However, the tools enabling high-input, high-volume commodity agriculture have also contributed to massive amounts of agricultural pollution, which has, in turn, negatively impacted human health.

Livestock and Human Health

According to the USDA's Agricultural Research Service, livestock and poultry grown in the United States produce nearly 1.4 billion tons of manure annually. All of that farm animal waste needs to go somewhere. Operators are supposed to apply only the amount that crops can use, but in reality, there is often too much manure, which is then applied beyond the ground's natural absorption rate, leading to runoff into water sources. The manure usually sits on-site in vast manure lagoons that can grow to the size of a football field. The lagoons contain a toxic stew of antibiotics residue, chemicals, and bacteria decomposing the waste, a medley that can take on a sickly hue. They’re often unlined and are prone to overflows, leaks, and spills, causing the contents to leach into the soil and groundwater. Once this mixture, chock-full of phosphorus and nitrogen, gets into a water body, it causes eutrophication, or the destructive overgrowth of algae.

Livestock and their manure also pollute the air. Manure emits ammonia that then combines with other air pollutants, creating tiny—and deadly—solid particles. These particles can cause heart and lung diseases and are said to account for at least 3.3 million deaths each year globally. In the United States, they account for 17,900 deaths as of 2021.

The widespread use of antibiotics in livestock farming is also contributing to the public health crisis of antibiotic resistance. Nearly two-thirds of antibiotics important to human medicine in the United States are sold for use in livestock, not people. The regular use of these drugs in the food and water of farm animals contributes to the rise and proliferation of antibiotic-resistant bacteria, which can spread from CAFOs via air and water and can end up in animal waste used to fertilize crops. Resistant bacteria can even "teach" resistance to other bacteria, and this process can take place anywhere bacteria are found, including in our homes and our guts.

Crop Agriculture and Human Health

Nitrogen-based fertilizers have been a major factor in the industrialization of agriculture, allowing high yields even on overtaxed land. But fertilizer has serious downsides for our water supplies and climate. When excess nitrogen makes its way into the atmosphere, it can become nitrous oxide, a potent greenhouse gas, or nitrogen oxide, which contributes to ground-level smog.

Runoff occurs when nutrient-rich material like fertilizer or manure makes its way into nearby rivers, oceans, and lakes, wreaking havoc on our freshwater and marine ecosystems. An excess of nutrients in a water system causes an overgrowth of algae. As algae die off, aerobic bacteria decompose them, consuming oxygen in the process and starving other marine life. Algae overgrowth can also block sunlight, disrupting the ecosystem below the water surface that relies on the sun for energy.

Farmers also routinely use pesticides—herbicides, insecticides, rodenticides, and fungicides—to keep away any unwanted weeds, insects, rodents, and fungi. But these toxic chemicals have serious side effects, including endocrine (hormone) and neurological disorders and cancer. Children are especially vulnerable to exposure and face the worst health impacts. Some of the most toxic pesticides, like chlorpyrifos, have been linked to developmental delays, lower IQs, and learning disabilities. Since becoming widespread in the past century, pesticides are routinely detected in 88% of our streams and rivers. More than 90% of Americans have pesticides in their bodies, circulating to all organs and systems.

Solutions

By 2050, the United Nations estimates that the global population will hit nearly 10 billion. Can we feed all these people without overtaxing our natural resources or destroying the planet in the process? It’s possible, but we’ll have to make significant shifts in the way we grow, raise, and eat food. Here are some steps we can all take:

• Eat more plant-based foods.
• Minimize consumption of red meat, our most carbon-intensive food.
• When choosing among restaurants, consider their records on antibiotic use in their meat supply.
• When buying animal products, buy products from animals raised without the regular use of medically important antibiotics.
• Opt for organic, especially with fruits and vegetables known to carry high amounts of pesticides like strawberries, spinach, and apples.
• Support local farmers practicing more sustainable growing methods.
• Buy "ugly" produce.
• Buy in bulk to limit packaging consumption.
• Start a "plant forward" initiative in your community and build meals around vegetables instead of meats.
• Grow your own food, without chemicals.

The impact of oil pollution on marine life

Oil spills are incredibly harmful to marine wildlife, including birds, mammals, fish, and shellfish. The impact of oil spills on marine life can be understood through two primary pathways: the oil itself and the response or cleanup operations.

The chemical constituents of oil are poisonous, and exposure to oil can cause both internal and external harm to organisms. Oil spills can lead to skin and eye irritation, and even smother some small species of fish or invertebrates. Additionally, oil can coat the feathers and fur of birds and mammals, reducing their ability to maintain body temperature and leading to hypothermia.

For marine birds and mammals, oil spills can be especially detrimental. Oil destroys the insulating ability of fur-bearing mammals, such as sea otters, and the water repellency of birds' feathers. Juvenile sea turtles can become trapped in oil and mistake it for food. Dolphins and whales are also at risk, as they can inhale oil, affecting their lungs, immune function, and reproduction. Many birds and animals ingest oil when they try to clean themselves, which can be poisonous and lead to poisoning.

Fish, shellfish, and corals may not be immediately exposed to oil spills, but if the oil is mixed into the water column, they can come into contact with it. Adult fish exposed to oil may experience reduced growth, enlarged livers, changes in heart and respiration rates, fin erosion, and reproduction impairment. Even when lethal impacts are not observed, oil can make fish and shellfish unsafe for human consumption.

Oil spills can also have indirect effects on marine life by causing changes in behavior. Animals may need to relocate their home ranges and spend more time foraging for food. Additionally, natural life cycles can be disrupted, particularly for rare species, which may become more susceptible to predation or future catastrophic events.

The magnitude of harm caused by oil spills varies depending on factors such as the amount of exposure, the pathway of exposure, the age and reproductive state of the animal, and the type of synthetic chemicals used in the cleanup process. Overall, oil spills have devastating consequences for marine life, and understanding their impact is crucial for developing effective response strategies to minimize ecological damage and promote the recovery of affected ecosystems.

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